Creationist Alternative to Big Bang

I stumbled on the Orion Foundation site recently. The site lays out a creationist "theory" of cosmology as an alternative to the Big Bang. As I have been talking about creationism in the classroom, and recently the ways creationists try to justify their "theories," I thought it would be an interesting exercise to work through what the Orion Foundation is proposing.

In what follows, I assume the reader has something of a working understanding of the Big Bang theory. Not necessarily the detailed physics of the theory, but at least a conceptual understanding. Edward Wright has a good tutorial on the subject, but is fairly detailed.

The Orion site publishes 10 papers that develop and justify their model. These papers, they say, were censored by the scientific community by being removed from a public preprint archive site. I will address each paper and try to summarize the points made therein. Then I will address each. (So if the readers sees something screwy without response, it is because the response will come later.) I will not attempt to address every single point. My intention is not so much to refute Orion's theory, but to study its methodology.

The papers are written by Robert Gentry.

The Theory
Paper 1 is the introduction to all that follows. One of the primary observations in support of the Big Bang theory is that of the 2.73K microwave background radiation. Recent observations have enabled researchers to measure the temperature of the CMB at a redshift of 2.34 and the results are nicely in line with the predictions of the Big Bang model. Gentry claims his model will reproduce these measurements, but with a different explanation for the redshift.

I'll try not to get too detailed at this point, but some explanation is in order. In 1929, Edwin Hubble measured the redshifts of spectra from many nearby galaxies and discovered a relationship between distance and redshift. He also found a lack of blueshifted spectra. Nearly everything except some of the nearest galaxies were reshifted. Interpreting the redshift as resulting from recessional velocity, Hubble concluded all the nearby galaxies were expanding away from the Earth. This, then, becomes one of the foundations of Big Bang, namely that the universe is expanding.

Later, Einstein's equations of general relativity were solved for some special cases (no one can solve them generally) for an expanding spacetime, and derived a relationship between redshift and distance. For small redshifts, which is the domain Hubble explored, these findings reproduced his. Conceptually, this is easy to understand. If we assume that spacetime itself is expanding over time, then distances will gradually increase. So light emitted at a wavelength of 1 cm will later be observed at a longer wavelength. Thus is the light redshifted. The longer the light travels, the more it will be redshifted as it will pick up more of the universal expansion. Therefore, there must be a relationship between redshift and distance.

So, again Hubble's discovery of the relationship between redshift and distance is a key foundation of Big Bang. Unfortunately we cannot independently measure distances to objects much further than those studied by Hubble to verify this relationship out to greater and greater distances/redshifts. Hence the problem of determining the age of the universe.

But key to this is that we interpret the redshift as resulting from cosmological expansion of spacetime. There are other ways of getting redshift. Having the galaxy moving away at some speed (a Doppler redshift) will also redshift the spectrum. Qualitatively, this is really not too different from the expansion understanding. Saying that the space between two objects is expanding is no different than saying the two objects are moving apart. The differences in the details between the two become important at high redshift. Gravity can produce redshifts as well.

In Paper 1, Gentry addresses the question of how to interpret redshift. He proposes the New Redshift Interpretation (NRI) in which "vacuum gravity repulsion causes Hubble-type recession of the galaxies away from" some universal center. Having proposed this, he spends the rest of the paper explaining the two foundational hypotheses of Big Bang: spacetime expansion, and the cosmological principle. (The latter states, essentially, that the Earth-bound observer does not occupy any special place in the universe, that what we observe here is no different than an observer elsewhere in the universe would observe.) He argues that these are assumptions which have not been tested and are fatally flawed.

In Paper 2, Gentry delves more deeply into the question of redshifts and the Big Bang interpretation thereof. He argues again, and in more detail, that this interpretation has not been tested. He also argues that Doppler effects also give a natural explanation for redshift, and is in fact the interpretation Hubble gave when he first studied the redshifts. Gentry points out that even seasoned professionals in the theory confuse the Doppler and expansion interpretations. (Given that, at least to some extent, this is an example of "6 of one, half dozen of the other," that's not too surprising.)

Gentry then discusses the idea of a center to the universe, arguing that Hubble's research proved it. After all, if everything is receding away from the Earth then the Earth must be at or very near the center of the universe.

In Paper 3, Gentry gets into the consequences of cosmological expansion. In particular, if spacetime itself is expanding, how can there be galaxies? Wouldn't this expansion have ripped them apart?

In Paper 4, Gentry addresses another consequence of redshift: energy loss. The energy of a photon is proportional to its frequency, the inverse of the wavelength. So as the wavelength increases, the energy decreases. But conservation of energy requires that this energy go somewhere. Where is it? Particles in motion also have a wavelength (the deBroglie wavelength) which must increase as spacetime expands. That means the particle's energy must be decreasing (lower momentum). Where does the energy go?

In Paper 5, Gentry returns to the expansion redshift to again say such interpretation has never been experimentally justified. The interaction of a photon with gravitational fields is examined and Gentry concludes that photons do not exchange energy with the gravitational field. So there is no gradual increase in wavelength and energy bleeds off.

In Paper 6, Gentry points out the issues arising from a time-variable Hubble "constant." He derives the equation dλ/dt = Hλ − H_eλ_e to describe the change in the wavelength over time, and the parameters with the e subscript are the values at the time of emission. So, the variation of the photon wavelength is dependent on the value of the Hubble constant at the time the photon was emitted. This, in turn, means that photons of the same wavelength will respond to universal expansion differently because if the different values of the Hubble constant at emission.

In Paper 7, Gentry again addresses the issue of a universal center. The spherical symmetry of the Hubble relationship, namely that everything is receding from the Earth, proves the existence of a nearby center. If the Earth were not at or near the center, there would be a dipole component to the distribution of redshift across the sky, i.e. some parts of the sky would show more redshift than other parts. Hubble understood this, but rejected the obvious conclusion, a violation of Ockham's [sic] razor. The distribution of gamma ray bursts in the sky also demonstrate the existence of a nearby center.

In Paper 8, Gentry presents his GENESIS model. I must admit it is not readily obvious what exactly this model is, so I cannot summarize it. (Section 2 of Paper 1 is apparently supposed to provide this summary, but is just a review of how redshifts have been conventionally interpreted.) As near as I can tell indirectly, the universe is pictured as a gigantic spherical cavity bounded by a wall of galaxies. The microwave background radiation is interpreted as gravitationally redshifted blackbody radiation.

The redshifts in galactic spectra are interpreted as arising from Doppler and gravitational effects. Gentry is able to derive observable properties and show that they agree with observation. He also makes some predictions, including the existence of some very high redshift galaxies.

In Paper 9, Gentry lists out the "smoking guns" of his theory. These are the seven key observational points which his theory explains. Much of this is repeated from Paper 8.

In Paper 10, Gentry lists out a laundry list of additional problems with the Big Bang theory.

Analysis
Several things are immediately obvious from this study. First off, there is nothing obviously creationist about this theory. How does visualizing a cavity bounded by a wall of galaxies fit Genesis any better than big bang? According to Paper 10, the creationist element of this theory is that is requires a cosmic center, something the Big Bang outright rejects, and that the Earth is placed near this center. I'll address this again below.

As pointed out before, the common technique to prove creationism is to pick out the flaws of the competition. In Orion's papers, we have eight dedicated to the flaws of Big Bang, and two to the creationist theory. Actually, there is only one since Paper 9 is essentially a repeat of Paper 8. Most, if not all, of the "smoking guns" for GENESIS can also be explained by Big Bang. There are certainly some predictions in the theory, but none have been born out yet.

Beyond that, Gentry makes a lot of circular arguments. For example, in his summary of small fluctuations of the microwave background, he concedes that Big Bang had an explanation as well, but then argues that since he has already invalidated Big Bang, those fluctuations are really proof of his theory and proof that the Big Bang is wrong.

Much is made in this work that Big Bang is based on assumptions which have not been verified. Well, welcome to science. All theories are based on some assumptions. The verification of those assumptions is that they lead to predictions which are born out experimentally. In electromagnetic theory, we assume the existence and certain properties of electrons and then work out predictions which are tested and verified. There is no direct evidence that electrons exist. The evidence is that the theories which govern the behavior of electrons lead to verifiable predictions. So, Gentry is objecting to the way science works. But then, Gentry does the same thing. He makes a big deal that the expansion interpretation of redshift is untested. But so is his Doppler and gravitational interpretation.

And objecting to the Cosmological Principle seems rather strange. The principle is required to do any cosmology. If we cannot assume that whatever we observe would be observed elsewhere in the universe, we cannot do any cosmology, Big Bang or GENESIS or anything else. All we know is what we can observe.

What about the center that Gentry is so proud of? His "proofs" of this center are derived from the spherical symmetry of the universe. That all the galaxies are flying away from the Earth means that there must be a center, right? No. Big Bang argues that, if the universe is infinitely large and the whole thing is expanding, then everything is flying away from everything else. This is the cosmological principle at work. He argues for a center, but I think he's really arguing for an edge to the universe, which is part of his picture. If there is an edge to the universe, then spherical symmetry would indeed require a center and that the Earth be near it. If we were away from the center and closer to the edge, then the sky would not be symmetric. But, if the universe is infinitely large, then spherical symmetry simply requires the cosmological principle.

Now, let us ask the question: is this science and should it be taught in the classroom? GENESIS is a theory which reproduces some results from Big Bang and predicts things that no one else has yet seen. Big Bang makes a lot of other predictions too, such as the relative abundance of hydrogen and helium in the universe, predictions for which GENESIS has no response, at least in the papers discussed here. So, at best, at this time GENESIS provides an alternative explanation for some things Big Bang already explains; no observation has been made which would distinguish the two pictures.

GENESIS is founded on a picture of the cosmos for which there is no justification, other than it can produce Big Bang-like results. (For example, postulating a cavity bounded by galaxies is the cosmic equivalent of an oven which will produce blackbody radiation, which we already know the microwave background to be. Furthermore, this wall of galaxies has fluctuations in temperature, for no apparent reason, which precisely mirror the fluctuations observed in the microwave background.) Big Bang is founded on assumptions, yes, but there are reasons to make those assumptions. The redshifts are assumed to be expansion redshifts because they emerge from solutions to the equations of General Relativity and because we can demonstrate the expected relationship of redshift and distance at short distance. The cosmological principle is required simply to do cosmology.

This point leads to a crucial distinction between Big Bang and GENESIS. The former makes a small number of justifiable assumptions, then proceeds to logically derive all sorts of observable properties of the universe. GENESIS presupposes an entire cosmos whose structure is rigged to produce expected results, then derives a few observable properties. Big Bang requires theoretical work to understand how galaxies form. GENESIS assumes they exist exactly as they are and provides no explanation of how they came to be. Big Bang requires theoretical work to understand how the elements came into being, how stellar engines got lit, etc. GENESIS simply says the elements exist, that stellar engines are running, etc.

So, the theory provides nothing new of value over what Big Bang provides. There are no observations yet made that would distinguish the two theories. The vast majority of the scientific community accepts the Big Bang as a working theory. Therefore, the answer to the question about its place in the classroom is no, GENESIS does not have a place in the classroom.

But, is it science? GENESIS starts from a contrived picture, but then appears to proceed fairly logically. (I haven't studied the detailed physics of GENESIS, so do not mistake that statement as something of an endorsement.) It then derives predictions, though nothing really specific. Big Bang said there should be some blackbody radiation at a really low temperature and which would be isotropic across the sky. GENESIS says there should be some very high redshift galaxies, much higher than could arise in a Big Bang universe. You can't take that prediction and do much with it other than look out for one. If a z=10 redshift galaxy is ever observed, does that prove GENESIS? No. It would raise questions about Big Bang, since such a galaxy would be appearing too early in the universe. But there is no reason in GENESIS to expect such a galaxy. It just allows it to exist. Is that science?

As to the scientific flaws Gentry describes, they can all be answered. The point about the change in wavelength requiring a "memory" of the Hubble constant at the time of emission assumes without justification that the Hubble constant is not a constant, but a time-variable parameter. The problem disappears by simply assuming the Hubble constant is a constant. The problem of conservation of energy in expansion is a relativistic effect.

The "vacuum gravity repulsion" Gentry talks about is not so screwy as it sounds. This is really just the cosmological constant Einstein arbitrarily added to general relativity. Recent observations of supernovae have justified that this constant is non-zero and an important part of the universe. Gentry argues that Big Bang did not include this constant, but there is nothing in the theory to demand a vanishing cosmological constant. It was assumed to be zero, but is now believed to be something else. It does not invalidate the Big Bang as Gentry claims.

That is not to say there are not significant scientific issues with Big Bang. There certainly are. So far as I know, no one can make galaxies emerge with clustering on the size scales observed in the time frame allowed. To me, that's long been the Achilles' Heel of Big Bang. The horizon problem requires inflation which in turn requires a perfectly flat universe, which is in conflict with observations. Reconciling observed density with a flat universe requires that the overwhelming majority of matter in the universe be totally undetectable dark matter, whose only purpose is to provide the required density to reconcile with inflation. And, of course, where did the Big Bang itself come from?

But the existence of flaw in the Big Bang does not justify GENESIS.